/*      $NetBSD: key.c,v 1.12 2001/05/17 01:02:17 christos Exp $        */

/*-
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Christos Zoulas of Cornell University.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "compat.h"
#if !defined(lint) && !defined(SCCSID)
#if 0
static char sccsid[] = "@(#)key.c       8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: key.c,v 1.12 2001/05/17 01:02:17 christos Exp $");
#endif
#endif /* not lint && not SCCSID */

/*
 * key.c: This module contains the procedures for maintaining
 *        the extended-key map.
 *
 *      An extended-key (key) is a sequence of keystrokes introduced
 *      with an sequence introducer and consisting of an arbitrary
 *      number of characters.  This module maintains a map (the el->el_key.map)
 *      to convert these extended-key sequences into input strs
 *      (XK_STR), editor functions (XK_CMD), or unix commands (XK_EXE).
 *
 *      Warning:
 *        If key is a substr of some other keys, then the longer
 *        keys are lost!!  That is, if the keys "abcd" and "abcef"
 *        are in el->el_key.map, adding the key "abc" will cause the first two
 *        definitions to be lost.
 *
 *      Restrictions:
 *      -------------
 *      1) It is not possible to have one key that is a
 *         substr of another.
 */
#include "sys.h"
#include <string.h>
#include <stdlib.h>

#include "el.h"

/*
 * The Nodes of the el->el_key.map.  The el->el_key.map is a linked list
 * of these node elements
 */
struct key_node_t {
        char            ch;             /* single character of key       */
        int             type;           /* node type                     */
        key_value_t     val;            /* command code or pointer to str,  */
                                        /* if this is a leaf             */
        struct key_node_t *next;        /* ptr to next char of this key  */
        struct key_node_t *sibling;     /* ptr to another key with same prefix*/
};

private int              node_trav(EditLine *, key_node_t *, char *,
    key_value_t *);
private int              node__try(EditLine *, key_node_t *, const char *,
    key_value_t *, int);
private key_node_t      *node__get(int);
private void             node__put(EditLine *, key_node_t *);
private int              node__delete(EditLine *, key_node_t **, char *);
private int              node_lookup(EditLine *, char *, key_node_t *, int);
private int              node_enum(EditLine *, key_node_t *, int);
private int              key__decode_char(char *, int, int);

#define KEY_BUFSIZ      EL_BUFSIZ


/* key_init():
 *      Initialize the key maps
 */
protected int
key_init(EditLine *el)
{

        el->el_key.buf = (char *) el_malloc(KEY_BUFSIZ);
        if (el->el_key.buf == NULL)
                return (-1);
        el->el_key.map = NULL;
        key_reset(el);
        return (0);
}


/* key_end():
 *      Free the key maps
 */
protected void
key_end(EditLine *el)
{

        el_free((ptr_t) el->el_key.buf);
        el->el_key.buf = NULL;
        /* XXX: provide a function to clear the keys */
        el->el_key.map = NULL;
}


/* key_map_cmd():
 *      Associate cmd with a key value
 */
protected key_value_t *
key_map_cmd(EditLine *el, int cmd)
{

        el->el_key.val.cmd = (el_action_t) cmd;
        return (&el->el_key.val);
}


/* key_map_str():
 *      Associate str with a key value
 */
protected key_value_t *
key_map_str(EditLine *el, char *str)
{

        el->el_key.val.str = str;
        return (&el->el_key.val);
}


/* key_reset():
 *      Takes all nodes on el->el_key.map and puts them on free list.  Then
 *      initializes el->el_key.map with arrow keys
 *      [Always bind the ansi arrow keys?]
 */
protected void
key_reset(EditLine *el)
{

        node__put(el, el->el_key.map);
        el->el_key.map = NULL;
        return;
}


/* key_get():
 *      Calls the recursive function with entry point el->el_key.map
 *      Looks up *ch in map and then reads characters until a
 *      complete match is found or a mismatch occurs. Returns the
 *      type of the match found (XK_STR, XK_CMD, or XK_EXE).
 *      Returns NULL in val.str and XK_STR for no match.
 *      The last character read is returned in *ch.
 */
protected int
key_get(EditLine *el, char *ch, key_value_t *val)
{

        return (node_trav(el, el->el_key.map, ch, val));
}


/* key_add():
 *      Adds key to the el->el_key.map and associates the value in val with it.
 *      If key is already is in el->el_key.map, the new code is applied to the
 *      existing key. Ntype specifies if code is a command, an
 *      out str or a unix command.
 */
protected void
key_add(EditLine *el, const char *key, key_value_t *val, int ntype)
{

        if (key[0] == '\0') {
                (void) fprintf(el->el_errfile,
                    "key_add: Null extended-key not allowed.\n");
                return;
        }
        if (ntype == XK_CMD && val->cmd == ED_SEQUENCE_LEAD_IN) {
                (void) fprintf(el->el_errfile,
                    "key_add: sequence-lead-in command not allowed\n");
                return;
        }
        if (el->el_key.map == NULL)
                /* tree is initially empty.  Set up new node to match key[0] */
                el->el_key.map = node__get(key[0]);
                        /* it is properly initialized */

        /* Now recurse through el->el_key.map */
        (void) node__try(el, el->el_key.map, key, val, ntype);
        return;
}


/* key_clear():
 *
 */
protected void
key_clear(EditLine *el, el_action_t *map, char *in)
{

        if ((map[(unsigned char)*in] == ED_SEQUENCE_LEAD_IN) &&
            ((map == el->el_map.key &&
            el->el_map.alt[(unsigned char)*in] != ED_SEQUENCE_LEAD_IN) ||
            (map == el->el_map.alt &&
            el->el_map.key[(unsigned char)*in] != ED_SEQUENCE_LEAD_IN)))
                (void) key_delete(el, in);
}


/* key_delete():
 *      Delete the key and all longer keys staring with key, if
 *      they exists.
 */
protected int
key_delete(EditLine *el, char *key)
{

        if (key[0] == '\0') {
                (void) fprintf(el->el_errfile,
                    "key_delete: Null extended-key not allowed.\n");
                return (-1);
        }
        if (el->el_key.map == NULL)
                return (0);

        (void) node__delete(el, &el->el_key.map, key);
        return (0);
}


/* key_print():
 *      Print the binding associated with key key.
 *      Print entire el->el_key.map if null
 */
protected void
key_print(EditLine *el, char *key)
{

        /* do nothing if el->el_key.map is empty and null key specified */
        if (el->el_key.map == NULL && *key == 0)
                return;

        el->el_key.buf[0] = '"';
        if (node_lookup(el, key, el->el_key.map, 1) <= -1)
                /* key is not bound */
                (void) fprintf(el->el_errfile, "Unbound extended key \"%s\"\n",
                    key);
        return;
}


/* node_trav():
 *      recursively traverses node in tree until match or mismatch is
 *      found.  May read in more characters.
 */
private int
node_trav(EditLine *el, key_node_t *ptr, char *ch, key_value_t *val)
{

        if (ptr->ch == *ch) {
                /* match found */
                if (ptr->next) {
                        /* key not complete so get next char */
                        if (el_getc(el, ch) != 1) {     /* if EOF or error */
                                val->cmd = ED_END_OF_FILE;
                                return (XK_CMD);
                                /* PWP: Pretend we just read an end-of-file */
                        }
                        return (node_trav(el, ptr->next, ch, val));
                } else {
                        *val = ptr->val;
                        if (ptr->type != XK_CMD)
                                *ch = '\0';
                        return (ptr->type);
                }
        } else {
                /* no match found here */
                if (ptr->sibling) {
                        /* try next sibling */
                        return (node_trav(el, ptr->sibling, ch, val));
                } else {
                        /* no next sibling -- mismatch */
                        val->str = NULL;
                        return (XK_STR);
                }
        }
}


/* node__try():
 *      Find a node that matches *str or allocate a new one
 */
private int
node__try(EditLine *el, key_node_t *ptr, const char *str, key_value_t *val, int ntype)
{

        if (ptr->ch != *str) {
                key_node_t *xm;

                for (xm = ptr; xm->sibling != NULL; xm = xm->sibling)
                        if (xm->sibling->ch == *str)
                                break;
                if (xm->sibling == NULL)
                        xm->sibling = node__get(*str);  /* setup new node */
                ptr = xm->sibling;
        }
        if (*++str == '\0') {
                /* we're there */
                if (ptr->next != NULL) {
                        node__put(el, ptr->next);
                                /* lose longer keys with this prefix */
                        ptr->next = NULL;
                }
                switch (ptr->type) {
                case XK_CMD:
                case XK_NOD:
                        break;
                case XK_STR:
                case XK_EXE:
                        if (ptr->val.str)
                                el_free((ptr_t) ptr->val.str);
                        break;
                default:
                        EL_ABORT((el->el_errfile, "Bad XK_ type %d\n",
                            ptr->type));
                        break;
                }

                switch (ptr->type = ntype) {
                case XK_CMD:
                        ptr->val = *val;
                        break;
                case XK_STR:
                case XK_EXE:
                        ptr->val.str = XSTRDUP (0, val->str);
                        break;
                default:
                        EL_ABORT((el->el_errfile, "Bad XK_ type %d\n", ntype));
                        break;
                }
        } else {
                /* still more chars to go */
                if (ptr->next == NULL)
                        ptr->next = node__get(*str);    /* setup new node */
                (void) node__try(el, ptr->next, str, val, ntype);
        }
        return (0);
}


/* node__delete():
 *      Delete node that matches str
 */
private int
node__delete(EditLine *el, key_node_t **inptr, char *str)
{
        key_node_t *ptr;
        key_node_t *prev_ptr = NULL;

        ptr = *inptr;

        if (ptr->ch != *str) {
                key_node_t *xm;

                for (xm = ptr; xm->sibling != NULL; xm = xm->sibling)
                        if (xm->sibling->ch == *str)
                                break;
                if (xm->sibling == NULL)
                        return (0);
                prev_ptr = xm;
                ptr = xm->sibling;
        }
        if (*++str == '\0') {
                /* we're there */
                if (prev_ptr == NULL)
                        *inptr = ptr->sibling;
                else
                        prev_ptr->sibling = ptr->sibling;
                ptr->sibling = NULL;
                node__put(el, ptr);
                return (1);
        } else if (ptr->next != NULL &&
            node__delete(el, &ptr->next, str) == 1) {
                if (ptr->next != NULL)
                        return (0);
                if (prev_ptr == NULL)
                        *inptr = ptr->sibling;
                else
                        prev_ptr->sibling = ptr->sibling;
                ptr->sibling = NULL;
                node__put(el, ptr);
                return (1);
        } else {
                return (0);
        }
}


/* node__put():
 *      Puts a tree of nodes onto free list using free(3).
 */
private void
node__put(EditLine *el, key_node_t *ptr)
{
        if (ptr == NULL)
                return;

        if (ptr->next != NULL) {
                node__put(el, ptr->next);
                ptr->next = NULL;
        }
        node__put(el, ptr->sibling);

        switch (ptr->type) {
        case XK_CMD:
        case XK_NOD:
                break;
        case XK_EXE:
        case XK_STR:
                if (ptr->val.str != NULL)
                        el_free((ptr_t) ptr->val.str);
                break;
        default:
                EL_ABORT((el->el_errfile, "Bad XK_ type %d\n", ptr->type));
                break;
        }
        el_free((ptr_t) ptr);
}


/* node__get():
 *      Returns pointer to an key_node_t for ch.
 */
private key_node_t *
node__get(int ch)
{
        key_node_t *ptr;

        ptr = (key_node_t *) el_malloc((size_t) sizeof(key_node_t));
        if (ptr == NULL)
                return NULL;
        ptr->ch = ch;
        ptr->type = XK_NOD;
        ptr->val.str = NULL;
        ptr->next = NULL;
        ptr->sibling = NULL;
        return (ptr);
}



/* node_lookup():
 *      look for the str starting at node ptr.
 *      Print if last node
 */
private int
node_lookup(EditLine *el, char *str, key_node_t *ptr, int cnt)
{
        int ncnt;

        if (ptr == NULL)
                return (-1);    /* cannot have null ptr */

        if (*str == 0) {
                /* no more chars in str.  node_enum from here. */
                (void) node_enum(el, ptr, cnt);
                return (0);
        } else {
                /* If match put this char into el->el_key.buf.  Recurse */
                if (ptr->ch == *str) {
                        /* match found */
                        ncnt = key__decode_char(el->el_key.buf, cnt,
                            (unsigned char) ptr->ch);
                        if (ptr->next != NULL)
                                /* not yet at leaf */
                                return (node_lookup(el, str + 1, ptr->next,
                                    ncnt + 1));
                        else {
                            /* next node is null so key should be complete */
                                if (str[1] == 0) {
                                        el->el_key.buf[ncnt + 1] = '"';
                                        el->el_key.buf[ncnt + 2] = '\0';
                                        key_kprint(el, el->el_key.buf,
                                            &ptr->val, ptr->type);
                                        return (0);
                                } else
                                        return (-1);
                                        /* mismatch -- str still has chars */
                        }
                } else {
                        /* no match found try sibling */
                        if (ptr->sibling)
                                return (node_lookup(el, str, ptr->sibling,
                                    cnt));
                        else
                                return (-1);
                }
        }
}


/* node_enum():
 *      Traverse the node printing the characters it is bound in buffer
 */
private int
node_enum(EditLine *el, key_node_t *ptr, int cnt)
{
        int ncnt;

        if (cnt >= KEY_BUFSIZ - 5) {    /* buffer too small */
                el->el_key.buf[++cnt] = '"';
                el->el_key.buf[++cnt] = '\0';
                (void) fprintf(el->el_errfile,
                    "Some extended keys too long for internal print buffer");
                (void) fprintf(el->el_errfile, " \"%s...\"\n", el->el_key.buf);
                return (0);
        }
        if (ptr == NULL) {
#ifdef DEBUG_EDIT
                (void) fprintf(el->el_errfile,
                    "node_enum: BUG!! Null ptr passed\n!");
#endif
                return (-1);
        }
        /* put this char at end of str */
        ncnt = key__decode_char(el->el_key.buf, cnt, (unsigned char) ptr->ch);
        if (ptr->next == NULL) {
                /* print this key and function */
                el->el_key.buf[ncnt + 1] = '"';
                el->el_key.buf[ncnt + 2] = '\0';
                key_kprint(el, el->el_key.buf, &ptr->val, ptr->type);
        } else
                (void) node_enum(el, ptr->next, ncnt + 1);

        /* go to sibling if there is one */
        if (ptr->sibling)
                (void) node_enum(el, ptr->sibling, cnt);
        return (0);
}


/* key_kprint():
 *      Print the specified key and its associated
 *      function specified by val
 */
protected void
key_kprint(EditLine *el, char *key, key_value_t *val, int ntype)
{
        el_bindings_t *fp;
        char unparsbuf[EL_BUFSIZ];
        static const char fmt[] = "%-15s->  %s\n";

        if (val != NULL)
                switch (ntype) {
                case XK_STR:
                case XK_EXE:
                        (void) fprintf(el->el_outfile, fmt, key,
                            key__decode_str(val->str, unparsbuf,
                                ntype == XK_STR ? "\"\"" : "[]"));
                        break;
                case XK_CMD:
                        for (fp = el->el_map.help; fp->name; fp++)
                                if (val->cmd == fp->func) {
                                        (void) fprintf(el->el_outfile, fmt,
                                            key, fp->name);
                                        break;
                                }
#ifdef DEBUG_KEY
                        if (fp->name == NULL)
                                (void) fprintf(el->el_outfile,
                                    "BUG! Command not found.\n");
#endif

                        break;
                default:
                        EL_ABORT((el->el_errfile, "Bad XK_ type %d\n", ntype));
                        break;
                }
        else
                (void) fprintf(el->el_outfile, fmt, key, "no input");
}


/* key__decode_char():
 *      Put a printable form of char in buf.
 */
private int
key__decode_char(char *buf, int cnt, int ch)
{
        if (ch == 0) {
                buf[cnt++] = '^';
                buf[cnt] = '@';
                return (cnt);
        }
        if (iscntrl(ch)) {
                buf[cnt++] = '^';
                if (ch == '\177')
                        buf[cnt] = '?';
                else
                        buf[cnt] = ch | 0100;
        } else if (ch == '^') {
                buf[cnt++] = '\\';
                buf[cnt] = '^';
        } else if (ch == '\\') {
                buf[cnt++] = '\\';
                buf[cnt] = '\\';
        } else if (ch == ' ' || (isprint(ch) && !isspace(ch))) {
                buf[cnt] = ch;
        } else {
                buf[cnt++] = '\\';
                buf[cnt++] = (((unsigned int) ch >> 6) & 7) + '0';
                buf[cnt++] = (((unsigned int) ch >> 3) & 7) + '0';
                buf[cnt] = (ch & 7) + '0';
        }
        return (cnt);
}


/* key__decode_str():
 *      Make a printable version of the ey
 */
protected char *
key__decode_str(char *str, char *buf, char *sep)
{
        char *b, *p;

        b = buf;
        if (sep[0] != '\0')
                *b++ = sep[0];
        if (*str == 0) {
                *b++ = '^';
                *b++ = '@';
                if (sep[0] != '\0' && sep[1] != '\0')
                        *b++ = sep[1];
                *b++ = 0;
                return (buf);
        }
        for (p = str; *p != 0; p++) {
                if (iscntrl((unsigned char) *p)) {
                        *b++ = '^';
                        if (*p == '\177')
                                *b++ = '?';
                        else
                                *b++ = *p | 0100;
                } else if (*p == '^' || *p == '\\') {
                        *b++ = '\\';
                        *b++ = *p;
                } else if (*p == ' ' || (isprint((unsigned char) *p) &&
                        !isspace((unsigned char) *p))) {
                        *b++ = *p;
                } else {
                        *b++ = '\\';
                        *b++ = (((unsigned int) *p >> 6) & 7) + '0';
                        *b++ = (((unsigned int) *p >> 3) & 7) + '0';
                        *b++ = (*p & 7) + '0';
                }
        }
        if (sep[0] != '\0' && sep[1] != '\0')
                *b++ = sep[1];
        *b++ = 0;
        return (buf);           /* should check for overflow */
}
